ACPI: EC: Don't init EC early if it has no _INI

Option to init EC early inserted to handle #8598 ASUS problem,
introduced several others.

EC driver in this particular case has fake _INI method, not present on
other machines, which don't need or break from this workaround, so lets use
its presence as a flag for early init.

http://bugzilla.kernel.org/show_bug.cgi?id=9262
http://bugzilla.kernel.org/show_bug.cgi?id=8598
https://bugzilla.novell.com/show_bug.cgi?id=334806

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 06b78e5e33a1..56afe13af592 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -881,12 +881,20 @@ int __init acpi_ec_ecdt_probe(void)
                 boot_ec->gpe = ecdt_ptr->gpe;
                 boot_ec->handle = ACPI_ROOT_OBJECT;
         } else {
+                /* This workaround is needed only on some broken machines,
+                 * which require early EC, but fail to provide ECDT */
+                acpi_handle x;
                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
                                                 boot_ec, NULL);
                 /* Check that acpi_get_devices actually find something */
                 if (ACPI_FAILURE(status) || !boot_ec->handle)
                         goto error;
+                /* We really need to limit this workaround, the only ASUS,
+                 * which needs it, has fake EC._INI method, so use it as flag.
+                 */
+                if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
+                        goto error;
         }
 
         ret = ec_install_handlers(boot_ec);